The precise date of Sir Bradley Wiggins's return to racing will depend on his recovery from the chest infection that forced him out of the Giro d'Italia on Friday, but Wiggins has been put down as a reserve in Team Sky's squad for the Critérium du Dauphiné stage race from 2-9 June, which means a comeback there is possible, with the Tour of Switzerland from 8 June another option.

Wiggins pulled out of the Giro d'Italia having spent several days on antibiotics for a chest infection and severe head cold. "The question now is whether he will recover quickly and what impact this has had on his condition, as that becomes clearer we will decide on the basis of that," said the Team Sky general manager, Dave Brailsford.

Brailsford also stated that Wiggins's withdrawal from the Giro will not change Sky's plan for the Tour de France, where Chris Froome is in pole position to lead the team. However, Brailsford confirmed that there is wriggle room within the scheme that Sky have laid down.

"Mostly things sort themselves out. A plan is your best guess on what will happen in the future. As it unfolds you correct it for reality," he said. In other words, a final decision on the precise hierarchy at Sky for the Tour will be taken only after a full assessment of the two potential leaders.

Brailsford explained that Wiggins began to fall ill on stage nine to Florence, run off in the wet and cold, but the team had been caught off guard until his condition worsened a few days later. "He definitely had something [in Florence]. He was chesty – [his team-mate] Christian Knees had a bad head cold; there were a couple of days when Christian was struggling, but the third day he improved.

"Our thinking was that there was a similar sort of thing going on with Brad, he would struggle but on the third or fourth day he will get better. But instead he got worse. At that point you have to be really careful. We've had guys in the past who've had chest infections which looked relatively innocent, you think: 'All right, carry on,' and they've developed pneumonia."

Brailsford added that as late as the day before his departure, Wiggins was looking forward to regaining time in the mountain time trial. The Team Sky head said that he and his team had no doubt that their leader arrived at the Giro d'Italia in the best condition possible, pointing to the Tour de France winner's performances in the two time trials in the first half of the race.

"He was super strong in the team time trial. Condition-wise he was in great shape. His weight was the same as in the past. If you look at the data from the [individual] time trial, the numbers from that were good when you broke it down. In general I don't think we were concerned about his fitness."

Brailsford explained that Wiggins's unexpectedly uneven ride in the individual time trial eight days ago was due to a slow puncture. "From the moment early on when he hit a pothole and thought there was something wrong with the steering, where in fact he had a slow puncture, there was a bit of confusion there and that led to a bit of tentativeness. When you look at it, from the pothole, which was 11 or 14 kilometres in, to the first check point at 30km he lost a minute, which is a lot of time."

"It's not just the wheel change; it's a multiplication of things, there is the deceleration and acceleration in and out of each corner, there's the question of whether you've damaged the bike, realising it's a slow puncture and how much does that take off. With the wheel change, it's not just the time on the side of the road, but the deceleration and re-acceleration, it's a different bike – you're thrown into that technical descent, which I don't think he's taking as coolly as everyone else, then there's that second section where he gained a minute and 10 seconds on everyone."

There was no obvious reason for Wiggins's sudden inability to descend on wet roads, which lost him time early on in the race. With no physical data to explain that Brailsford admitted he was stumped. "I don't think I've got an explanation. It was out of character, you couldn't have predicted that. When you think on day one, Ryder [Hesjedal] attacked downhill and there were six of them away for a period – well Brad was one of the six. In [the Tour of] Catalunya he attacked downhill – there's nothing wrong with his descending when he wants to, when he's on it. We're all speculating."

The toughness of the Giro course this year has surprised some, but Brailsford maintains that Sky and Wiggins were not thrown on the back foot by the route, but by the fact that their leader fell sick. "We've done the Giro every year since we started. The course wasn't a surprise to anybody. It is a tough, brutal race, the climbing is about being good on steeper gradients, which is different to the climbs on the Tour de France – it wasn't that. If you're ill, you're ill."